From 7b0d792ce13c0e894ee32a94b321b329724c9a25 Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Thu, 19 Sep 2019 17:54:10 -0700 Subject: cputlb: Move ROM handling from I/O path to TLB path It does not require going through the whole I/O path in order to discard a write. Reviewed-by: David Hildenbrand Signed-off-by: Richard Henderson --- accel/tcg/cputlb.c | 36 +++++++++++++++++++++--------------- 1 file changed, 21 insertions(+), 15 deletions(-) (limited to 'accel') diff --git a/accel/tcg/cputlb.c b/accel/tcg/cputlb.c index 028eebcb44..404ec57a4e 100644 --- a/accel/tcg/cputlb.c +++ b/accel/tcg/cputlb.c @@ -577,7 +577,8 @@ static void tlb_reset_dirty_range_locked(CPUTLBEntry *tlb_entry, { uintptr_t addr = tlb_entry->addr_write; - if ((addr & (TLB_INVALID_MASK | TLB_MMIO | TLB_NOTDIRTY)) == 0) { + if ((addr & (TLB_INVALID_MASK | TLB_MMIO | + TLB_DISCARD_WRITE | TLB_NOTDIRTY)) == 0) { addr &= TARGET_PAGE_MASK; addr += tlb_entry->addend; if ((addr - start) < length) { @@ -745,7 +746,6 @@ void tlb_set_page_with_attrs(CPUState *cpu, target_ulong vaddr, address |= TLB_MMIO; addend = 0; } else { - /* TLB_MMIO for rom/romd handled below */ addend = (uintptr_t)memory_region_get_ram_ptr(section->mr) + xlat; } @@ -822,16 +822,17 @@ void tlb_set_page_with_attrs(CPUState *cpu, target_ulong vaddr, tn.addr_write = -1; if (prot & PAGE_WRITE) { - if ((memory_region_is_ram(section->mr) && section->readonly) - || memory_region_is_romd(section->mr)) { - /* Write access calls the I/O callback. */ - tn.addr_write = address | TLB_MMIO; - } else if (memory_region_is_ram(section->mr) - && cpu_physical_memory_is_clean( - memory_region_get_ram_addr(section->mr) + xlat)) { - tn.addr_write = address | TLB_NOTDIRTY; - } else { - tn.addr_write = address; + tn.addr_write = address; + if (memory_region_is_romd(section->mr)) { + /* Use the MMIO path so that the device can switch states. */ + tn.addr_write |= TLB_MMIO; + } else if (memory_region_is_ram(section->mr)) { + if (section->readonly) { + tn.addr_write |= TLB_DISCARD_WRITE; + } else if (cpu_physical_memory_is_clean( + memory_region_get_ram_addr(section->mr) + xlat)) { + tn.addr_write |= TLB_NOTDIRTY; + } } if (prot & PAGE_WRITE_INV) { tn.addr_write |= TLB_INVALID_MASK; @@ -904,7 +905,7 @@ static uint64_t io_readx(CPUArchState *env, CPUIOTLBEntry *iotlbentry, mr = section->mr; mr_offset = (iotlbentry->addr & TARGET_PAGE_MASK) + addr; cpu->mem_io_pc = retaddr; - if (mr != &io_mem_rom && mr != &io_mem_notdirty && !cpu->can_do_io) { + if (mr != &io_mem_notdirty && !cpu->can_do_io) { cpu_io_recompile(cpu, retaddr); } @@ -945,7 +946,7 @@ static void io_writex(CPUArchState *env, CPUIOTLBEntry *iotlbentry, section = iotlb_to_section(cpu, iotlbentry->addr, iotlbentry->attrs); mr = section->mr; mr_offset = (iotlbentry->addr & TARGET_PAGE_MASK) + addr; - if (mr != &io_mem_rom && mr != &io_mem_notdirty && !cpu->can_do_io) { + if (mr != &io_mem_notdirty && !cpu->can_do_io) { cpu_io_recompile(cpu, retaddr); } cpu->mem_io_vaddr = addr; @@ -1125,7 +1126,7 @@ void *probe_access(CPUArchState *env, target_ulong addr, int size, } /* Reject I/O access, or other required slow-path. */ - if (tlb_addr & (TLB_NOTDIRTY | TLB_MMIO | TLB_BSWAP)) { + if (tlb_addr & (TLB_NOTDIRTY | TLB_MMIO | TLB_BSWAP | TLB_DISCARD_WRITE)) { return NULL; } @@ -1617,6 +1618,11 @@ store_helper(CPUArchState *env, target_ulong addr, uint64_t val, return; } + /* Ignore writes to ROM. */ + if (unlikely(tlb_addr & TLB_DISCARD_WRITE)) { + return; + } + haddr = (void *)((uintptr_t)addr + entry->addend); /* -- cgit v1.2.3